Which two ratios form a proportion? A) 1 : 3 and 6 : 3 B) 1 : 3 and 3 : 6 C) 3 : 1 and 9 : 3 D) 3 : 1 and 3 : 9

the correct answer is C

Option (C)

Step-by-step explanation:

Two ratios are proportional when one is a multiple of the other.

Consider A: 1 : 3 and 6 : 3

6 : 3 is equivalent to 3 (2 : 1). 1 : 3 and 3 (2 : 1) are not proportional.

Consider B : 1 : 3 and 3 : 6.

3 : 6 is equivalent to 3 (1 : 2).

Again the two ratios are not proportional.

Now for Option C : 3 : 1 and 9 : 3.

9 : 3 is equivalent to 3 (3 : 1). Clearly, the two ratios are proportional.

Hence, Option C is the answer.

For similar reasons Option D can be eliminated as well.